Lesser known early forms of metal

I'm looking for obscurish late 60's, early 70's bands that sound strangely metal. This stems from my discovery of a song from the band Cromagnon. Caledonia has this weird pagan aura, with lo-fi guitars and harsh vocals. Basically psychedelic rock that accidently turned into Burzum or Twilight of the Gods era-Bathory, though obviously inferior to the two. Unfortunately, this is the only song on their only album that sounds remotely metal.

Flower Travellin' Band was a unique psyche doom group that made one metal album, Satori. The rest of their stuff is either poppy, or covers of bands like King Crimson and Black Sabbath. Decent compositions that show their east asian heritage.

A couple of Pink Floyd's earlier songs have some screams and gutteral talking. I can only imagine this would have sounded quite intense for the time of their release. Not quite proto metal, but noteworthy.

A dark and brooding album of classical inspired progressive rock. There are parts with rather brutal growling etc. and the overall atmosphere is rather "ritualistic" so to say. The compositions sometimes make me think of early Unholy material.

I've heard Univers Zero described as Immolation if they had formed one hundred years earlier, and that description fits the bill pretty well. Their Ceux du Dehors album is pretty much brutal death metal of the dissonant/atmospheric Immolation/Incantation-ish vein, but completely instrumental and with oboes and violins instead of guitars and blastbeats.

Sir Lord Baltimore is probably the first true heavy metal band outside of Black Sabbath.

Bedemon is probably the first true underground metal to exist.

This genre has always excited me because for these concepts to have existed at this stage, they would truly been honest, extreme representations of what become cliche and common-place later. This makes it less rock in its derogatory form than most extreme metal.

Strangely enough, the main riff in "Transilvanian Hunger" carries an eerie semblance to the main melody in their ballad "Come Down." This spurs me to wonder whether Darkthrone derived their "musical inspiration" not just from Autopsy, Celtic Frost and Bathory, even back in the good ol' days.

I've been meaning to check out Goblin, Coven, Antonius Rex, Jacula, and related projects, but have yet to get around to it. Apparently a lot of this stuff comes from Italy.

I'm so glad someone mentioned Goblin. This is one of my favorite bands. Obviously outside of the metal genre, but possessing some qualities of metal/punk in the electronic/synth (and sometimes guitar) performance and composition. This soundtrack material reminds me of music that's written akin to Emperor and their sense of fantasy and music's evocative and imaginative capabilities.